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Consider the following statements: Phase controlled converters at small values of output voltage have 1. Large harmonics in utility system 2. Poor power factor 3. High efficiency 4. Notches in line voltage waveform Which of the above statements are correct?

Consider the following statements: Phase controlled converters at small values of output voltage have 1. Large harmonics in utility system 2. Poor power factor 3. High efficiency 4. Notches in line voltage waveform Which of the above statements are correct? Correct Answer 1, 2 and 4

  • Phase controlled converters at small values of output voltage inject large harmonics into the utility system.
  • These converters produce notches in the line voltage waveform.
  • Because of high ripple content in the converter output, motor heating and commutation problems are serious.
  • Due to the non-sinusoidal nature of current & switching action, there is more possibility of interference with communication networks.
  • At small values of output voltage, these operate at a very poor power factor as well as a poor displacement factor.

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